1 /*
2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "vp9/encoder/vp9_treewriter.h"
12
tree2tok(struct vp9_token * tokens,const vp9_tree_index * tree,int i,int v,int l)13 static void tree2tok(struct vp9_token *tokens, const vp9_tree_index *tree,
14 int i, int v, int l) {
15 v += v;
16 ++l;
17
18 do {
19 const vp9_tree_index j = tree[i++];
20 if (j <= 0) {
21 tokens[-j].value = v;
22 tokens[-j].len = l;
23 } else {
24 tree2tok(tokens, tree, j, v, l);
25 }
26 } while (++v & 1);
27 }
28
vp9_tokens_from_tree(struct vp9_token * tokens,const vp9_tree_index * tree)29 void vp9_tokens_from_tree(struct vp9_token *tokens,
30 const vp9_tree_index *tree) {
31 tree2tok(tokens, tree, 0, 0, 0);
32 }
33
convert_distribution(unsigned int i,vp9_tree tree,unsigned int branch_ct[][2],const unsigned int num_events[])34 static unsigned int convert_distribution(unsigned int i, vp9_tree tree,
35 unsigned int branch_ct[][2],
36 const unsigned int num_events[]) {
37 unsigned int left, right;
38
39 if (tree[i] <= 0)
40 left = num_events[-tree[i]];
41 else
42 left = convert_distribution(tree[i], tree, branch_ct, num_events);
43
44 if (tree[i + 1] <= 0)
45 right = num_events[-tree[i + 1]];
46 else
47 right = convert_distribution(tree[i + 1], tree, branch_ct, num_events);
48
49 branch_ct[i >> 1][0] = left;
50 branch_ct[i >> 1][1] = right;
51 return left + right;
52 }
53
vp9_tree_probs_from_distribution(vp9_tree tree,unsigned int branch_ct[][2],const unsigned int num_events[])54 void vp9_tree_probs_from_distribution(vp9_tree tree,
55 unsigned int branch_ct[/* n-1 */][2],
56 const unsigned int num_events[/* n */]) {
57 convert_distribution(0, tree, branch_ct, num_events);
58 }
59